<!DOCTYPE html>
<html>
	<head>
		<meta charset="UTF-8">
		<title></title>
	</head>
	<body>
		<script>
			var arr = [[1,2,3,4],[7,8,2],[7,2,7,6,3,3],[1],[2,4,3]];
			function getMax(a){
				var max = a[0].length;
				var index = 0;
				for(var i=1;i<a.length;i++){
					if(max<a[i].length){
						max = a[i].length;
						index = i;
					}
				}
//				return max;
//				return {index:index,max:max,arr:a[index]};
				return a[index];
			}
			console.log(getMax(arr));
		</script>
	</body>
</html>
